It's not carbon, but if you look on the site I linked to above, the writer claims it's lighter than their carbon stem. I have the original shim, so you can use it with the modern fatty bars or the retro slim.
This top-of-the-range Easton aluminium alloy stem weighs less than the firm's EC90 carbon composite model. As an added bonus it is stiff, very stiff.
Quality is ﬁrst rate, performance is ﬁrst rate and the ease of ﬁtting and quality of the instructions are, you guessed it, also ﬁrst rate.
Everything is as it should be on a near-perfect stem, although we would like to see domed-head Allen bolts on the steerer clamp rather than the cap-head ones ﬁtted as standard.
The price is a little high compared with the likes of the Hope, Syntace and Thomson offerings, but there is no mistaking that this is a remarkably light, high-performance stem.